Mammut Sphere Eigerjoch Sleeping Bag: 20 Degree Down

Sleep smarter.

When you're hauling heavy loads into challenging alpine terrain, every ounce counts. And knowing that you're bringing a down jacket anyways, Mammut designed the Sphere Eigerjoch 20 Sleeping Bag to work with your down jacket to reduce bulk and weight without sacrificing warmth. Plus, smartly designed openings let you wear the bag around camp so you don't need to pack tons of extra layers on cold nights.

The idea is that you will be wearing your down jacket inside your sleeping bag, so there's less down in the upper area where your jacket will be, and zippered arm openings let you read, play cards, or cook without leaving the toastiness of your bag. If that wasn't enough, there's also a zippered opening at the bottom that not only offers ventilation on warmer nights, but lets you walk around camp in toasty comfort. Side gear loops let you lock in the foot opening at two different heights so you're not tripping over your bag.

  • Ultralight and warm bag designed to work with down jacket
  • Two half-zip side openings allow you to take both arms out
  • Zippered bottom opening allows vents and lets you stand
  • Side gear loops lock foot opening at two different heights
  • Reduced down in upper area where jacket is worn
  • 95/5 goose down insulation is ultralight, warm, and compressible
  • Performance hood allows full visibility while completely closed
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